WHEN you drive past the completed the Tamparuli-Ranau Road, cross the Tamparuli Bridge, or see a high-rise emerging in Kota Kinabalu, you may not think about the soil or rock beneath those structures. Yet, the ground is the silent foundation of everything we build.
If it fails, the structures above are at risk. In Sabah – a land of rugged mountains, deep valleys, and diverse geology – the professionals who safeguard the ground are engineering geologists (Geologists) and geotechnical engineers.
Their titles may sound similar, but their roles are distinct. Understanding the difference between them is like understanding the difference between a doctor who diagnoses a patient and a surgeon who performs the operation.
Both are vital, but each serves a different purpose.
Why They Matter in SabahSabah’s landscape makes these professions especially critical. Along the west coast – from Papar to Beaufort the ground is often made up of soft material that compresses easily, causing settlement and cracks in roads and buildings.
In the Crocker Range, steep slopes and heavy tropical rainfall create a high risk of landslides that can cut off major routes like the Kimanis–Keningau Road. In the east coast districts such as Sandakan, Lahad Datu, and Tawau, coastal and reclaimed lands pose foundation challenges due to soft and waterlogged soil.
Meanwhile, areas like Ranau and Kundasang are among the most geologically active in Malaysia. Earthquakes, landslides, and ground movement are common, especially after the 2015 Mount Kinabalu earthquake.
With climate change bringing more intense rainfall and erosion, the risks are increasing – making the collaboration between engineering geologists and geotechnical engineers more essential than ever.
Geotechnical Engineers – The Ground BuildersGeotechnical engineers are civil engineers who specialize in understanding and designing with soil and rock. Their responsibility is to ensure that every structure built in Sabah – from bridges to retaining walls, from high-rise towers to rural roads – has a foundation that can safely support it.
If a condominium is planned in Kota Kinabalu, the professional geotechnical engineer will design the foundation; determines how deep the piles must be to reach stable bearing strata.
If the government constructs a new stretch of the Pan Borneo Highway across hilly terrain, the geotechnical engineer designs slope protection systems and drainage to prevent landslides.
When water treatment plants or reservoirs are built in Tuaran or Beaufort, the geotechnical engineer ensures the soil will not cause settlement or instability.
Geotechnical engineers are the “surgeons” of the ground – they take measurements, test the soil, run calculations, and then design the solutions that make construction safe.
Geologists – The Storytellers of the EarthGeologists, by contrast, are geoscientists who interpret the earth’s story. They study how the land / material was formed, identify the type and condition of rocks and soils, and assess geological hazards. Their work provides crucial information that guides engineers in making design decisions.
Before the geotechnical engineer begins the design, the geologist investigates: What type of rock lies beneath the site? Are there faults or fractures that could cause instability? Is the slope material likely to weather, creep, or collapse?In Kundasang, for instance, geologists map unstable slopes and identify areas prone to landslides after prolonged rainfall.
In Lahad Datu or Tawau, they study soft soil deposits and old river channels that can lead to uneven settlement. In Ranau, they analyse active fault zones and recommend setbacks for safe development.
If the geotechnical engineer is the surgeon, the engineering geologist is the doctor who reads the X-ray and makes the diagnosis.
Training and RegistrationThe two professions also differ in their education and professional registration.
Geotechnical engineers begin with a degree in civil engineering, learning about structures, hydraulics, and soil mechanics. Many later specialise in geotechnical engineering through postgraduate studies. They are registered with the Board of Engineers Malaysia (BEM) under the Registration of Engineers Act 1967 and may earn the title of Professional Engineer (Ir.) and also with PEPC certificate.Engineering geologists begin with a degree in geology or geosciences, studying minerals, rock formation, geomorphology, and natural hazards. Some pursue postgraduate qualifications in engineering geology.
They are registered with the Board of Geologists Malaysia (BoG) under the Geologists Act 2008 and may earn the title of Professional Geologist (P. Geol.).
In essence, engineers are trained to design and build, while geologists are trained to understand and explain the earth material.
Legal Roles and Professional Practice in SabahUnder Malaysian law, the Registration of Engineers Act 1967 mandates that any engineering design, including geotechnical design, must be carried out or endorsed by a Professional Engineer with the PEPC certificate.
Thus, the presence of a geotechnical engineer is legally required in most infrastructure and construction projects in Sabah.
By contrast, the Geologists Act 2008 formally recognises professional geologists but does not make their participation mandatory in every project.
Their role typically comes through collaboration – when a Professional Engineer engages an engineering geologist to provide geological input, particularly for complex or hazard-prone sites.
However, ignoring geological advice can be costly. In Sabah, numerous slope failures and soil movement incidents have occurred because geological conditions were not adequately studied before construction.
Working Together – The Sabah WaySuccessful projects in Sabah depend on both professions working hand in hand.
For example: A dam in Babagon, district of Penampang, the geologist first maps the bedrock and checks for fractures or karst features that could lead to leakage. The geotechnical engineer then designs the dam foundation and seepage control systems based on that geological input. For hillside development near Penampang, the engineering geologist assesses slope stability and identifies weak rock zones, while the geotechnical engineer designs retaining structures and proper drainage systems. During the Pan Borneo Highway construction, geologist identified unstable slopes, and engineers implemented soil nails, retaining walls, and surface drains to stabilise them.Neither profession can complete the task alone – their synergy ensures safety, resilience, and cost-effectiveness.
In conclusionGeologists focus on historical understanding of Earth’s materials and processes, while Geotechnical Engineers apply this knowledge to solve engineering problems and ensure the stability and safety of structures and construction projects.
